Front type thermostat mounting



June 7, 1949. I J, SANDERS 7 2,472,728

FRONT TYPE THERMOSTAT MOUNTING Filed March 1, 1946 2 Sheets-Sheet lINVEN TOR. f/mare Jana are BY MM AA-QWM A r ram/V57 June 7, 1949. E. J.SANDERS 2,472,728

FRONT TYPE THERMOSTAT MOUNTING I Filed March 1, 1946 2 Sheets-Sheet 2 Il N V EN TOR. E/marz c/. Jam/era JMMW ATTORNEY Patented June 7, 1949FRONT TYPE THEBMOSTAT MOUNTING Elmore J. Sanders, San Gabriel, Calif.,assignor to Evans Products Company, Detroit, Mich., a

corporation of Delaware Application March 1, 1946, Serial No. 651,071

1 Claim.

This invention relates to variable pitch fan blade assemblies used inconnection with a cooling system of an internal combustion engine, thepitch of the fan blades varying in accordance with the requirements asindicated by the temperature of the circulating cooling liquid.

An object of this invention is to produce a compact and efiicient fanassembly in which the pitch of the fan blades are varied in response tothe transverse movement of a thermostat disposed in the liquid coolingsystem to substantially reduce the power required to operate the fanwhen a lesser amount of air circulation is needed.

Another object of this invention is to produce an improved variablepitch fan blade assembly in which an adapter mounts the thermostat andliquid housing on the front of the fan assembly in a manner enabling therotational movements of the fan assembly in relation to the associatedthermostat housing.

Another object of this invention is to provide a liquid temperatureactuating means for varying the pitch of the fan blades, said meansbeing mounted on the front end of the fan assembly where less support isnecessary and enabling the use of a simplified and easily accessibleunit.

Other objects and advantages will hereinafter appear and for purposes ofillustration but not of limitation, an embodiment of the invention isshown in the accompanying drawings in which:

Figure 1 is a perspective front view of a fan assembly rotatably mountedon the front end of a stationary internal combustion engine and showingthe thermostat housing stationarily mounted on the front end of the fanassembly.

Figure 2 is a horizontal sectional view taken through the fan assemblyand the attached thermostat members in which many of the members are notsectioned for purposes of clarity in the illustration. The view is takenalong the line 2-2 of Figure 1.

Figure 3 is a sectional view taken along the line 3-3 of Figure 2showing the eccentrically mounted pin in relation to the centrallymounted fan blade for transmitting substantially linear movement of theone to rotational movement of the other effecting fan blade turningmovements.

In the illustrated embodiment of the invention In indicates an internalcombustion engine having a crankshaft (not shown) which mounts a beltpulley II, the peripheral grooves i2 thereof being operatively engagedby multiple continuous belts I3 'for transmitting the powered rotationalmovements of the pulley to the other units ll associated with the engineIt.

As illustrated, the fan assembly F hereinafter more fully described,comprises split hub sections l5 held together by bolts [5a and enclosedby side casings 15b secured to said assembled hub by bolts I50. Bolts l6interconnecting the belt pulley II with the rearward casing l5b securelymounts the fan assembly for rotational movement concomitantly with thebelt pulley. It is to be understood, however, that rotary movements maybe imparted to the fan assembly by other crankshaft take-01f means, onesuch other means comprising a separately mounted shaft and pulley.

Associated with the forward portion of the fan assembly F is athermostat housing or jacket ll which comprises a metallic cup-shapedmember [8 having a pair of laterally extending tubes l9 and 20 one ofwhich l9 conducts the cooling liquid from the fluid source into thethermostat housing, the other tube 20 providing the return passage forthe liquid. Thus the continuous flow of cooling liquid which is forcedthrough the housing by the water pump (not shown) in the fluid system,maintains the housing at the circulating liquid temperature. The fluidsource from which the control liquid is bled may include any part of thefluid system which is desired to be controlling, for example, the fluidat the radiator outlet, the engine jacket, the water pump, or the like.'An outwardly disposed annular flange 2i integral with the inner edgeportion of the cup-shaped member l8 abuts a similarly dimensionedannular flange 22 having apertures 23 therein in registry with apertures23a in the flange 2| through which multiple bolts and nuts 24 operate tosecure said flanged members in the assembled relation providing a liquidtight seal. The annular flange 22 forms a part of the disc shaped member25 which closes the open end of the cup-shaped housing member l8 and hasan aperture 26 in the center portion thereof for receipt of a part ofthe thermostat casing 27a. Disposed within the described housing is athermostat 21 of the type which imparts transverse shifting movement toa shaft 28 in response to changes in temperatures. Such thermostats arecommercially available, a suitable unit being presently marketed underthe designation Vernatherm, and since it forms no part of the presentinvention detailed description thereof is considered unnecessary.Suflice it to say that the shaft 28 is encased by a fluid packing 29which in turn is tightly enclosed by an axially aligned sleeve 30 whichforms an extension of the thermostat casing 21a, said sleeve 30, fittingthrough the aperture 26, is screw threaded at 3l'on its outer surfacefor threaded engagement with the screw threaded spindle 32 which issecurely connected, as by brazing, to the central portion of the discshaped closing member 25. Thus the thermostat 21 is securely positionedin the thermostat housing II. The spindle 32 is in the shape of anaxially aligned elongate cylinder having its inner end enclosed, butwith an aperture 33 therein, enabling translatory shifting movement ofan enlarged shaft extension 34 connected concentrically with thethermostat shaft 28. It is obvious that a liquid tight housing isprovided in which the body portion of the thermostat is disposed, theattached spindle 32 operating as a mounting member for the thermostatand the housing for connection with the fan blade assembly.

The thermostat housing, as described, is staticnarily mounted on theforward portion of the normally rotating fan assembly and for thispurpose it is necessary to provide an adapter 35 having an annularflange 35 integral with the central portion of an axially aligned cupshaped retaining member 31, said annular flange 36 having multipleapertures 38 therein for receipt of bolts 35 securing said flange to theend casing 40 of the fan assembly effecting rotatative movement of saidretainer 31 concomitantly with said fan assembly. An aperture 4| in thebase 42 of the cup shaped member 3! permits the disposition of thethermostat housing spindle 32 therethrough, the remaining down-turnedportion of the base 42 operating as an abutment resisting the outwardmovement of anti-friction bearings 43 retained within the cup shapedportion. Outward movement of the thermostat housing and attached spindleis prevented by the stop nut 44 screw threadably engaged to the screwthreaded end portion 45 of the spindle 32. The anti-friction bearingthus riding between the adapter connected to the fan assembly and thespindle connected to the thermostat housing permits free rotativemovement of the fan blade assembly in relation to the latter.

For detailed description of the fan blade assembly F reference is herebymade to a co-pending application Serial No. 564,278, filed November 20,1944, on which Patent No. 2,437,810 of March 16, 1948 has been issued,and entitled "Variable pitch fan blade assembly wherein the essentialfeatures of the mechanism for varying the pitch of the fan blades is setforth and further description thereof is not considered necessary exceptas the disposition of the adapter and thermostat efiect the relationshipof the fan assembly elements. Suflice it to say that the fan bladeassembly F comprises a series of fan blades each of which carries a stubshaft 5| mounted between ball bearings 52 disposed within a flanged cupshaped retainer 53 which seats in recessed annular grooves in the splitfan hub l5 permitting rotative movement of the fan blade in relation tothe fan hub assembly F. Each stub shaft 5| has a screw threaded centralby a jack nut 56 which positions the roller bear-' ing 52 and forces thewithdrawal of a concentrically depending center pin 51 which tightlyfits an aperture 58 in'the fiat disc 58 rotative in the hub opening 60.A key 6| insertable through registered apertures in the pin 51 and thedisc 59 maintains the elements in the assembled relation. Each disccarries an eccentrically disposed pin 63 which is operatively engaged byan aperture 63a formed in the outer surface of an portion 55 engaged Itis evident that transverse shifting movement of the actuating sleevewill impart rotative movement to the fan blade in relation to thesupporting fan hub assembly. Transverse shifting movement is imparted tothe actuating sleeve 54 by means of the thermostat 21 through theinterconnected axially aligned shafts 28 and 34. For this purpose asleeve 59 is threadably positioned on the outer end portion of the shaft34, said sleeve having a shoulder 10 forming an abutment which bearsagainst one end of a series of antifn'ction bearings 'H disposed betweensaid sleeve 69 and the actuating sleeve 64 enabling rotary movement ofthe latter in relation to the former. The other end of eachanti-friction bearing abuts against a shoulder 12 formed on the innersurface of the actuating sleeve, thus rearward shifting movement of thethermostat shaft 28 is concomitantly imparted to the actuating sleeve54. Movement of the actuating sleeve in the opp site direction iseffected by a conically shaped coil spring 13 having the smaller endbearing against the end portion of the crank-shaft and the largerendportion disposed about the conically shaped nose 68, the outer end ofsaid spring seating in the recessed groove 85 of the actuating sleeve.

From the description it will be manifest that the pitch of the severalfan blades is automatically changed in accordance with the temperatureof the cooling liquid which comes in contact with the thermostat 21.Thus the element may be initially adjusted such that when thetemperature of the cooling liquid is relatively low, the pitch of thefan blades will be such as to direct a minimum stream of air through theradiator or to the engine, thus saving considerably in the powerexpended in operating the fan assembly. When the temperature of thecooling liquid rises, the pitch of the fan blade is proportionatelychanged to direct a greater stream of air to the radiator or engine.

It is manifest that I have produced an automatically operated variablepitch fan blade assembly in which the thermostat responsive to thetemperature of the cooling water is mounted in a liquid tight jacket onthe forward end of the fan assembly. The resultant longitudinal shiftingmovement of the thermostat is imparted to the fan blade assembly forvarying the pitch of the fan blade irrespective of the turning movementsof the fan assembly in relation to the stationarily mounted thermostathousing. In this sense an important feature of this invention resides inthe adapter means for mounting the thermostat containing housing on theforward end of a rotating fan assembly.

I have also produced a compact and easily assembled unit in which thefan elements are assembled between split hub sections, the adapterconnecting the thermostat housing to the fan assembly permittingassembly and adjustment of the thermostat unit without modification ofthe fan assembly, and since the thermostat housing does not supportother engine members, a

rigid and sturdy support is deemed unnecessary enabling simplificationof the structure and mounting.

It is to be understood that numerous changes in the details ofconstruction, arrangement,,and operation may be effected withoutdeparting from the spirit of the invention especially as defined in thesubmitted claim.

What I claim is:

A variable pitch fan for an internal combustion engine, comprising, ahub assembly having a periphery and front and rear sides, means on saidrear side for aflixing the hub assembly to a rotating member forrotation therewith, fan blades projecting radially from said periphery,bearing means mounting said blades on said periphery for rotation abouttheir radial axes,

crank means eccentric of said radial axes on the inner ends of saidblades, an activating member common toall of said crank means withinsaid hub assr'nbly, said activating member rotating with said hubassembly, bearing means slidably mounting said activating member withinsaid hub assembly for axial movement with respect to said hub assembly,whereby, when said activating member moves axially, said blades areturned about their radial axes, a combined rotary and axial thrustbearing centrally disposed in said activating member including an outerbearing sleeve rotating with said hub assembly about an inner bearingmember, the front side of said hub assembly having an axial openingtherein, a second combined rotary and axial thrust bearmg having anouter sleeve amxed within said opening and rotating about an innersleeve, and

a thermostatic control assembly comprising a sleeve, means for afllxingsaid sleeve within the inner ring of said second bearing member with thefront end of said sleeve projecting be 0nd the front side of said hubassembly, a liquid v ight housing amxed to the front end of said's'leeve,

an axial shaft extending from the inner bearing member of said firstcombination bearing to said chamber, thermal-responsive means in saidchamber for moving said shaft axially upon changes of temperature ofsaid cooling liquid, and means for connecting the interiorof saidhousing to a source of cooling liquid.

- EIMORE J. SANDERS.

REFERENCES orrnn The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Embery et al Dec. 3, 1935

